Hope that 11 missing crew members from drilling rig Deepwater Horizon would be found had mostly faded by Friday morning although rescuers continued to search. While some feared an environmental catastrophe, oil sheen on the Gulf of Mexico appeared to be from the explosion and not a leaking well, officials said.

On Tuesday night the rig, which is owned and operated by Transocean Inc. on behalf of BP plc, experienced an explosion and fire (see Daily GPI, April 23).

U.S. Coast Guard Rear Admiral Mary Landry, who heads the Eighth Coast Guard District, which is conducting the search, told CBS News the 11 missing crew members were most likely on the rig at the time of the explosion. We are “holding out hope that we may find one of these 11 missing people,” she said Friday morning. “We’re planning to search throughout the day today, through daylight hours today.”

Landry said the rig is not on top of the wellhead but is nearby. “At this point in time we’re confident that the sheen that we’re working with [on the water] is residual from the explosion…We have not seen any visible signs of crude emanating from the well. We’ll continue to monitor that situation,” Landry said.

Smith International Inc. said five employees of M-I SWACO, which it owns with Schlumberger Ltd., were aboard Deepwater Horizon at the time of the explosion. Three are safe; two remained missing Friday. “We are deeply saddened by this tragic event. Our thoughts and prayers are with our colleagues and the loved ones of those affected,” said Smith International CEO John Yearwood.

U.S. Sen. Mary Landrieu (D-LA) commended the search efforts and has called for an investigation of the incident. “Even as the rescue efforts continue, it is clear that the U.S. Coast Guard and the Minerals Management Service should conduct a swift and thorough investigation into this incident. It is critical that these agencies examine what went wrong and the environmental impact this incident has created. These findings should be reported to Congress as soon as possible.”

U.S. Sen. Lisa Murkowski (R-AK) said she was “dismayed” to learn of the rig’s sinking Thursday. “We do not yet know how this development will affect the marine environment, but I understand all emergency spill response units in the Gulf have been mobilized,” she said. “My staff and I are receiving regular briefings from the Coast Guard, the Minerals Management Service and BP. I will continue to closely monitor this situation and I have offered the full resources of my office to aid all of those affected by this tragedy.”

©Copyright 2010Intelligence Press Inc. All rights reserved. The preceding news reportmay not be republished or redistributed, in whole or in part, in anyform, without prior written consent of Intelligence Press, Inc.